Global Patent Index - EP 0775245 A4

EP 0775245 A4 2000-08-30 - MODULAR ROTARY DRILL BIT

Title (en)

MODULAR ROTARY DRILL BIT

Title (de)

MODULARER DREHBOHRMEISSEL

Title (fr)

TREPAN ROTATIF MODULAIRE

Publication

EP 0775245 A4 (EN)

Application

EP 95928785 A

Priority

  • US 9510050 W
  • US 28744694 A

Abstract (en)

[origin: US5439068A] A rotary cone drill bit for forming a borehole having a one-piece bit body with a lower portion having a convex exterior surface and an upper portion adapted for connection to a drill string. The drill bit will generally rotate around a central axis of the bit body. A number of support arms are preferably attached to pockets formed in the bit body and depend therefrom. Each support arm has an inside surface with a spindle connected thereto and an outer surface. Each spindle projects generally downwardly and inwardly with respect to the longitudinal axis of the associated support arm and the central axis of the bit body. A number of cone cutter assemblies equal to the number of support arms are mounted respectively on each of the spindles. The spacing between each of the support arms along with their respective length and width dimensions are selected to enhance fluid flow between the cutter cone assemblies mounted on the respective support arms and the lower portion of the bit body. A lubricant reservoir is preferably provided in each support arm to supply lubricant to one or more bearing assemblies disposed between each cutter cone assembly and its associated spindle. Either matching openings and posts or matching keyways and keys may be used to position and align a portion of each support arm within its associated pocket during fabrication of the resulting drill bit.

IPC 1-7 (main, further and additional classification)

E21B 10/08; E21B 10/20; E21B 10/24

IPC 8 full level (invention and additional information)

E21B 10/20 (2006.01); E21B 10/24 (2006.01)

CPC (invention and additional information)

E21B 10/24 (2013.01); E21B 10/20 (2013.01)

Citation (search report)

Designated contracting state (EPC)

GB IT

EPO simple patent family

US 5439068 A 19950808; US 5439068 B1 19970114; AU 3241495 A 19960307; EP 0775245 A1 19970528; EP 0775245 A4 20000830; EP 0775245 B1 20031029; MX 9700653 A 19970430; WO 9605403 A1 19960222

INPADOC legal status


2006-04-26 [GBPC] GB: EUROPEAN PATENT CEASED THROUGH NON-PAYMENT OF RENEWAL FEE

- Effective date: 20050808

2005-08-08 [PG25 GB] LAPSED IN A CONTRACTING STATE ANNOUNCED VIA POSTGRANT INFORM. FROM NAT. OFFICE TO EPO

- Ref Country Code: GB

- Free text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

- Effective date: 20050808

2005-08-08 [PG25 IT] LAPSED IN A CONTRACTING STATE ANNOUNCED VIA POSTGRANT INFORM. FROM NAT. OFFICE TO EPO

- Ref Country Code: IT

- Free text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

- Effective date: 20050808

2004-10-20 [26N] NO OPPOSITION FILED

- Effective date: 20040730

2004-07-07 [PGFP GB] POSTGRANT: ANNUAL FEES PAID TO NATIONAL OFFICE

- Ref Country Code: GB

- Payment date: 20040707

- Year of fee payment: 10

2004-06-30 [REG GB 732E] AMENDMENTS TO THE REGISTER IN RESPECT OF CHANGES OF NAME OR CHANGES AFFECTING RIGHTS (SECT. 32/1977)

2003-10-29 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: B1

- Designated State(s): GB IT

2003-10-29 [REG GB FG4D] EUROPEAN PATENT GRANTED

2002-04-17 [17Q] FIRST EXAMINATION REPORT

- Effective date: 20020228

2000-08-30 [A4] SUPPLEMENTARY SEARCH REPORT

- Effective date: 20000717

2000-08-30 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A4

- Designated State(s): GB IT

2000-08-30 [RIC1] CLASSIFICATION (CORRECTION)

- Free text: 7E 21B 10/08 A, 7E 21B 10/24 B, 7E 21B 10/20 B

1997-05-28 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 19970205

1997-05-28 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): GB IT